JP2011070934A - Wiring circuit board and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiring circuit board suppressing heat generation of an extraction electrode part, and also to provide a fuel cell equipped with the same. <P>SOLUTION: Collecting parts 3a, 3b are formed on a first insulating part 2c. Extraction conductor parts 4a, 4b are formed to extend from sides of the collecting parts 3a, 3b onto third insulating parts 2d, 2e passing over the first insulating part 2c and second insulating parts 2a, 2b. Extraction electrode parts 10a, 10b are formed integrally with the leading end parts of the extraction conductor parts 4a, 4b above the third insulating parts 2d, 2e. The width of the extraction electrode part 10a is set wider than that of the extraction conductor part 4a, and the width of the extraction electrode part 10b is set wider than that of the extraction conductor part 4b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a printed circuit board and a fuel cell.

  Mobile devices such as mobile phones are required to have small and high capacity batteries. Therefore, development of a fuel cell capable of obtaining a high energy density as compared with a conventional battery such as a lithium secondary battery has been advanced. As the fuel cell, for example, there is a direct methanol fuel cell.

  In a direct methanol fuel cell, methanol is decomposed by a catalyst to generate hydrogen ions. Electric power is generated by reacting the hydrogen ions with oxygen in the air. In this case, chemical energy can be converted into electrical energy very efficiently, and a very high energy density can be obtained.

  In such a direct methanol fuel cell, for example, a flexible printed circuit board (hereinafter abbreviated as FPC board) is provided as a current collecting circuit (see, for example, Patent Document 1).

  A conventional FPC board used for a fuel cell has, for example, a configuration in which a pair of conductor layers are formed on one surface of a base insulating layer. Lead electrodes are provided to extend from the pair of conductor layers.

  The FPC board is bent with the one surface on which the conductor layer is formed facing inward. A membrane electrode assembly composed of a polymer electrolyte membrane, a fuel electrode and an air electrode is sandwiched between the conductor layers of the bent FPC board.

  In this state, the bent FPC board is accommodated in the casing of the fuel cell except for the lead electrode portion. Various external circuits such as electronic components are electrically connected to the portion of the extraction electrode exposed from the housing.

  Methanol is supplied to the fuel electrode of the membrane electrode assembly, and air is supplied to the air electrode of the membrane electrode assembly. Thereby, in the fuel electrode, methanol is decomposed into hydrogen ions and carbon dioxide by the catalyst, and electrons are generated.

  Hydrogen ions decomposed from methanol pass through the polymer electrolyte membrane and reach the air electrode, and react with oxygen in the air supplied to the air electrode on the catalyst. Thereby, electrons are consumed while water is generated at the air electrode. Thereby, electrons move between the conductor layers of the FPC board, and power is supplied to the external circuit.

JP 2004-200064 A

  When power is supplied from the fuel cell to the external circuit, a current flows intensively through the extraction electrode. As a result, the lead electrode generates more heat than the other parts. Heat generation in the extraction electrode becomes a factor that reduces the power generation efficiency of the fuel cell. Further, the peripheral portion of the extraction electrode may be deformed due to heat generation in the extraction electrode.

  An object of the present invention is to provide a printed circuit board capable of suppressing heat generation of the lead electrode portion and a fuel cell including the same.

  (1) A wired circuit board according to a first invention is a wired circuit board used in a fuel cell, comprising an insulating layer and a conductor layer provided on the insulating layer, wherein the conductor layer is a current collector And a lead conductor part extending from the current collector part and a lead electrode part provided at the tip of the lead conductor part, and the maximum width of the lead electrode part is larger than the maximum width of the lead conductor part It is.

  In the wired circuit board, a conductor layer including a current collector, a lead conductor, and a lead electrode is formed on the insulating layer. In this case, the maximum width of the extraction electrode portion is larger than the maximum width of the extraction conductor portion. Thereby, the resistance value of the extraction electrode portion is sufficiently reduced.

  Therefore, when this printed circuit board is used for a fuel cell, heat generation in the extraction electrode portion can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell from being reduced due to heat generated by the extraction electrode portion. Further, it is possible to prevent the peripheral portion of the extraction electrode portion from being deformed by the heat generation of the extraction electrode portion.

  (2) The lead electrode portion may be configured to be bendable along one or a plurality of lines substantially parallel to the extending direction of the lead conductor portion.

  In this case, the space occupied by the lead electrode portion can be reduced by bending the lead electrode portion along one or more lines substantially parallel to the extending direction of the lead conductor portion. Thereby, when this printed circuit board is used for a fuel cell, it is possible to improve the degree of freedom of arrangement of the fuel cell while suppressing heat generation in the extraction electrode portion.

  (3) The lead electrode portion has a first portion having a width equal to that of the lead conductor portion and extending in the extending direction from the lead conductor portion, and a second portion provided on one side of the first portion. Further, it may be configured to be bendable along a boundary line between the first portion and the second portion.

  In this case, the extraction electrode portion can be easily bent along the boundary line between the first portion and the second portion. Thereby, the occupation space of the extraction electrode part can be surely reduced while suppressing the heat generation in the extraction electrode part.

  (4) The width of the second part may be equal to the width of the first part.

  In this case, the lead electrode portion can be bent so that the first portion and the second portion entirely overlap. Thereby, the width of the lead electrode portion can be increased without increasing the space occupied by the lead electrode portion.

  (5) The lead electrode portion is further provided on one side of the second portion, further includes a third portion having a width equal to that of the first portion, and the second portion and the third portion It may be configured to be bendable along the boundary line.

  In this case, since the width of the extraction electrode portion becomes larger, the resistance value of the extraction electrode portion becomes sufficiently smaller. Thereby, the heat generation in the extraction electrode portion can be more sufficiently suppressed.

  Further, the lead electrode portion is bent along the boundary line between the first portion and the second portion, and the lead electrode portion is bent along the boundary line between the second portion and the third portion. By doing so, the space occupied by the extraction electrode portion can be sufficiently reduced.

  (6) The lead electrode portion further includes a fourth portion provided on the other side of the first portion, and is configured to be bendable along a boundary line between the first portion and the fourth portion. Also good.

  In this case, since the width of the extraction electrode portion becomes larger, the resistance value of the extraction electrode portion becomes sufficiently smaller. Further, the extraction electrode portion can be easily bent along the boundary line between the first part and the second part and the boundary line between the first part and the fourth part. Thereby, the occupation space of the extraction electrode part can be surely reduced while suppressing the heat generation in the extraction electrode part.

  (7) The sum of the width of the second portion and the width of the fourth portion may be equal to the width of the first portion.

  In this case, the lead electrode portion can be bent so that one surface of the first portion is covered with the second portion and the fourth portion. Thereby, the width of the lead electrode portion can be increased without increasing the space occupied by the lead electrode portion.

  (8) The width of each of the second portion and the fourth width may be equal to the width of the first portion.

  In this case, the lead electrode portion can be bent so that the first, second, and fourth portions entirely overlap each other. Thereby, the width of the extraction electrode portion can be sufficiently increased without increasing the space occupied by the extraction electrode portion.

  (9) A wired circuit board according to a second invention is a wired circuit board used in a fuel cell, comprising an insulating layer and a conductor layer provided on the insulating layer, wherein the conductor layer includes: Provided at the second current collector, the first and second lead conductors extending from the first and second current collectors, and the first and second lead conductors, respectively. And the insulating layer and the conductor layer are configured to be bendable between the first and second current collectors such that the conductor layer is located inside, The maximum widths of the first and second lead electrode portions are larger than the maximum widths of the first and second lead conductor portions, respectively.

  In the printed circuit board, a conductor layer including the first and second current collecting parts, the first and second lead conductor parts, and the first and second lead electrode parts is formed on the insulating layer. .

  When this wired circuit board is used for a fuel cell, the insulating layer and the conductive layer of the wired circuit board are bent between the first and second current collectors so that the conductive layer is located inside. The first and second extraction electrode portions are extracted outside the fuel cell.

  In this case, since the maximum width of the extraction electrode portion is larger than the maximum width of the extraction conductor portion, the resistance value of the extraction electrode portion is sufficiently small. Therefore, heat generation in the extraction electrode portion can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell from being reduced due to heat generated by the extraction electrode portion. Further, it is possible to prevent the peripheral portion of the extraction electrode portion from being deformed by the heat generation of the extraction electrode portion.

  (10) A fuel cell according to a third invention includes a battery element, a wired circuit board according to the second invention, and a housing that houses the wired circuit board and the battery element. The element is housed in the housing with the first current collector and the second current collector sandwiched therebetween, and the first and second lead electrode portions are externally disposed so as not to overlap each other. It was drawn out to.

  In the printed circuit board of the fuel cell, a conductor layer comprising first and second current collectors, first and second lead conductors, and first and second lead electrode parts is formed on the insulating layer. It is formed.

  The insulating layer and the conductor layer of the printed circuit board are bent between the first and second current collectors so that the conductor layer is located inside. A battery element is disposed between the first and second current collectors of the bent printed circuit board.

  In this state, the printed circuit board and the battery element are housed in the casing, and are drawn out from the casing so that the first and second lead electrode portions of the printed circuit board do not overlap each other. An external circuit is connected to the first and second lead electrode portions.

  In this case, since the first and second lead electrode portions do not overlap each other, an external circuit can be easily and reliably connected to the first and second lead electrode portions. Thereby, the connection reliability between the printed circuit board and the external circuit is improved.

  Further, since the maximum width of the extraction electrode portion is larger than the maximum width of the extraction conductor portion, the resistance value of the extraction electrode portion becomes sufficiently small. Therefore, heat generation in the extraction electrode portion can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell from being reduced due to heat generated by the extraction electrode portion. Further, it is possible to prevent the peripheral portion of the extraction electrode portion from being deformed by the heat generation of the extraction electrode portion.

  According to the present invention, the resistance value of the extraction electrode portion is sufficiently small. Thereby, heat generation in the extraction electrode portion can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell from being reduced due to heat generated by the extraction electrode portion. Further, it is possible to prevent the peripheral portion of the extraction electrode portion from being deformed by the heat generation of the extraction electrode portion.

It is a figure which shows the structure of the flexible wiring circuit board which concerns on this Embodiment. It is process sectional drawing for demonstrating the manufacturing method of a flexible printed circuit board. It is process sectional drawing for demonstrating the manufacturing process of a flexible printed circuit board. It is a figure which shows the structure of the fuel cell using the flexible printed circuit board of FIG. It is a figure for demonstrating the effect | action in the fuel cell of FIG. It is a figure which shows the 1st modification of a drawer | drawing-out part. It is a figure which shows the 2nd modification of a drawer | drawing-out part. It is a figure which shows the 3rd modification of a drawer | drawing-out part. It is a top view which shows the other modification of a flexible printed circuit board.

  Hereinafter, a printed circuit board and a fuel cell according to an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a flexible printed circuit board having flexibility will be described as an example of the printed circuit board.

(1) Configuration of Flexible Wiring Circuit Board FIG. 1A is a plan view of the flexible wiring circuit board according to the present embodiment. 1B is a cross-sectional view taken along line AA of the flexible printed circuit board of FIG. 1A, and FIG. 1C is a cross-sectional view taken along line BB of the flexible printed circuit board shown in FIG. It is. In the following description, the flexible printed circuit board is abbreviated as an FPC board.

  As shown in FIG. 1A, the FPC board 1 includes a base insulating layer 2 made of polyimide, for example. The base insulating layer 2 includes a first insulating portion 2c, second insulating portions 2a and 2b, and third insulating portions 2d and 2e.

  The first insulating portion 2c has a rectangular shape, and strip-shaped second insulating portions 2a and 2b are provided so as to protrude outward from one side of the first insulating portion 2c. Rectangular third insulating portions 2d and 2e are provided at the tips of the second insulating portions 2a and 2b, respectively. Hereinafter, the one side of the first insulating portion 2c and the other side parallel thereto are called side sides, and the other pair of sides perpendicular to the side sides of the first insulating portion 2c are called end sides. Further, a direction parallel to the side of the first insulating portion 2c is referred to as a side direction, and a direction parallel to the end of the first insulating portion 2c is referred to as an end side direction.

  The width of the third insulating portion 2d is larger than the width of the second insulating portion 2a, and the width of the third insulating portion 2e is larger than the width of the second insulating portion 2b. Here, the widths of the second insulating portions 2a and 2b and the third insulating portions 2d and 2e refer to the lengths of the second insulating portions 2a and 2b and the third insulating portions 2d and 2e in the side direction.

  A bent portion B1 is provided in the first insulating portion 2c of the base insulating layer 2 along the edge direction so as to bisect the first insulating portion 2c. As will be described later, the insulating base layer 2 is bent along the bent portion B1. The bent portion B1 may be, for example, a linear shallow groove, or a linear mark or the like. Alternatively, as long as the FPC board 1 can be bent at the bent portion B1, there may be nothing in the bent portion B1.

  The second insulating portion 2a and the third insulating portion 2d are provided so as to protrude outward from the side of one region (hereinafter referred to as the first region) of the first insulating portion 2c with the bent portion B1 as a boundary. The second insulating portion 2b and the third insulating portion 2e protrude outward from the side of the other region (hereinafter referred to as the second region) of the first insulating portion 2c with the bent portion B1 as a boundary. Is provided.

  A plurality (six in this example) of openings H1 are formed in the first region of the first insulating portion 2c. A plurality (six in this example) of openings H2 are formed in the second region of the first insulating portion 2c.

  On one surface of the base insulating layer 2, a conductor layer 3 made of, for example, copper is formed. The conductor layer 3 includes current collecting portions 3a and 3b, lead conductor portions 4a and 4b, and lead electrode portions 10a and 10b.

  The current collector 3a is formed on the first region of the first insulating portion 2c, and the current collector 3b is formed on the second region of the first insulating portion 2c. Each of the current collectors 3a and 3b has a rectangular shape, and has a pair of side sides along the side direction and a pair of end sides along the end side direction.

  The lead conductor part 4a is formed so as to extend in the edge direction from the side of the current collecting part 3a to the third insulating part 2d through the first region of the first insulating part 2c and the second insulating part 2a. The The lead conductor portion 4b is formed so as to extend from the side of the current collecting portion 3b in the end side direction through the second region of the first insulating portion 2c and the second insulating portion 2b to the third insulating portion 2e. The

  The lengths of the lead conductor portions 4a and 4b in the end side direction are preferably greater than 0 mm and not greater than 10 mm, and more preferably greater than 0 mm and not greater than 5 mm.

  The lead electrode portion 10a is integrally formed with the tip portion of the lead conductor portion 4a on the third insulating portion 2d, and the lead electrode portion 10b is integrally formed with the tip portion of the lead conductor portion 4b on the third insulating portion 2e. Formed.

  The width of the lead electrode portion 10a is set larger than the width of the lead conductor portion 4a, and the width of the lead electrode portion 10b is set larger than the width of the lead conductor portion 4b. Here, the widths of the lead conductor portions 4a and 4b and the lead electrode portions 10a and 10b refer to the lengths of the lead conductor portions 4a and 4b and the lead electrode portions 10a and 10b in the side direction.

  An opening H11 having a diameter larger than that of the opening H1 is formed in the portion of the current collector 3a on the opening H1 of the base insulating layer 2. An opening H12 having a diameter larger than that of the opening H2 is formed in the portion of the current collector 3b on the opening H2 of the base insulating layer 2.

  A covering layer 6a is formed on the first region of the first insulating portion 2c so as to cover the current collecting portion 3a of the conductor layer 3, and the second insulating member 2c of the first insulating portion 2c is covered so as to cover the current collecting portion 3b of the conductor layer 3. A coating layer 6b is formed on the region. The coating layers 6a and 6b are made of a resin composition containing carbon. Specifically, epoxy or polyimide containing carbon is used as the material of the coating layers 6a and 6b. Carbon is not limited to carbon black, and various carbon materials such as graphite can be used.

  The covering layer 6a is in contact with the upper surface of the base insulating layer 2 in the opening H11 of the current collector 3a. In addition, the coating layer 6b is in contact with the upper surface of the base insulating layer 2 in the opening H12 of the current collector 3b. Thereby, the current collectors 3a and 3b are not exposed in the openings H11 and H12.

  A cover insulating layer 8a is formed on the first region of the first insulating portion 2c and the second insulating portion 2a so as to cover the lead conductor portion 4a of the conductor layer 3, and so as to cover the lead conductor portion 4b of the conductor layer 3. A cover insulating layer 8b is formed on the second region of the first insulating portion 2c and on the second insulating portion 2b. The insulating cover layers 8a and 8b are made of polyimide, for example. In this case, the upper and side surfaces of the lead conductor portions 4a and 4b are covered with the insulating cover layers 8a and 8b so that the lead conductor portions 4a and 4b are not exposed.

  A plating layer 11a is formed on the third insulating portion 2d so as to cover the lead electrode portion 10a, and a plating layer 11b is formed on the third insulating portion 2e so as to cover the lead electrode portion 10b. The plating layers 11a and 11b are made of nickel and gold, for example. In this case, the upper surfaces and side surfaces of the extraction electrode portions 10a and 10b are covered with the plating layers 11a and 11b so that the extraction electrode portions 10a and 10b are not exposed.

  The third insulating portion 2d, the extraction electrode portion 10a, and the plating layer 11a constitute the extraction portion 5a, and the third insulation portion 2e, the extraction electrode portion 10b, and the plating layer 11b constitute the extraction portion 5b.

  In the lead portion 5a, a pair of bent portions B2 are formed on an extension line of one side and the other side of the second insulating portion 2a along the end side direction. Similarly, in the lead portion 5b, a pair of bent portions B2 are formed on the extended lines of one side and the other side of the second insulating portion 2b along the end side direction.

  Hereinafter, the portion of the lead portion 5a between the pair of bent portions B2 is referred to as an inner region 9a, and the portion of the lead portion 5a outside the pair of bent portions B2 is referred to as an outer region 7a. Further, a portion of the lead portion 5b between the pair of bent portions B2 is referred to as an inner region 9b, and a portion of the lead portion 5b outside the pair of bent portions B2 is referred to as an outer region 7b.

  In this example, the width of the inner region 9a is approximately equal to the sum of the widths of the pair of outer regions 7a, and the width of the inner region 9b is approximately equal to the sum of the widths of the pair of outer regions 7b. Here, the widths of the inner regions 9a and 9b and the outer regions 7a and 7b refer to the lengths of the inner regions 9a and 9b and the outer regions 7a and 7b in the side direction.

  Note that the bent portion B2 may be, for example, a linear shallow groove, or may be a linear mark or the like, similar to the bent portion B1. Or as long as the drawer | drawing-out parts 5a and 5b can be bent in bending part B2, there may be nothing in bending part B2.

(2) Manufacturing Method of FPC Wiring Circuit Board Next, a manufacturing method of the FPC board 1 shown in FIG. 1 will be described. 2 to 3 are process cross-sectional views for explaining a method for manufacturing the FPC board 1. 2 (a) to (c) and FIGS. 3 (d) to (f), the upper part shows the manufacturing process in the section corresponding to the cross section taken along the line AA of FIG. The manufacturing process in the location corresponding to 1 BB line cross section is shown.

  First, as shown in FIG. 2A, a two-layer base material having an insulating film 20 made of, for example, polyimide and a conductor film 21 made of, for example, copper is prepared. The thickness of the insulating film 20 is preferably 5 μm or more and 50 μm or less, and more preferably 12.5 μm or more and 25 μm or less. The thickness of the conductor film 21 is preferably 2 μm or more and 70 μm or less, and more preferably 5 μm or more and 35 μm or less.

  Next, as shown in FIG. 2B, an etching resist 22 having a predetermined pattern is formed on the conductor film 21. The etching resist 22 is formed, for example, by forming a resist film on the conductor film 21 using a dry film resist or the like, exposing the resist film in a predetermined pattern, and then developing the resist film.

  Next, as shown in FIG. 2C, the region of the conductive film 21 except the region under the etching resist 22 is removed by etching. Next, as shown in FIG. 3D, the etching resist 22 is removed with a stripping solution. As a result, current collecting portions 3a and 3b, lead conductor portions 4a and 4b (FIG. 1), and lead electrode portions 10a and 10b are formed on the insulating film 20.

  Subsequently, as shown in FIG. 3E, coating layers 6a and 6b made of a resin composition containing, for example, carbon black are formed on the insulating film 20 so as to cover the current collectors 3a and 3b. The thickness of the coating layers 6a and 6b is preferably 0.2 μm or more and 50 μm or less, and more preferably 5 μm or more and 30 μm or less.

  Further, insulating cover layers 8a and 8b (FIG. 1) are formed so as to cover the lead conductor portions 4a and 4b (FIG. 1) (FIG. 1). The thickness of the insulating cover layers 8a and 8b is preferably 0.2 μm or more and 50 μm or less, and more preferably 5 μm or more and 30 μm or less.

  Further, plating layers 11a and 11b made of, for example, a nickel plating layer and a gold plating layer are formed so as to cover the extraction electrode portions 10a and 10b. The thickness of the nickel plating layer of the plating layers 11a and 11b is preferably 0.3 μm or more and 8 μm or less, and more preferably 0.5 μm or more and 6 μm or less. The thickness of the gold plating layer is preferably 0.03 μm or more and 1 μm or less, and more preferably 0.05 μm or more and 0.5 μm or less.

  Next, as shown in FIG. 3F, the FPC substrate 1 is completed by cutting the insulating film 20 into a predetermined shape.

  2 and 3, the case where the conductor layer 3 (the current collecting portions 3a and 3b, the lead conductor portions 4a and 4b, and the lead electrode portions 10a and 10b) is formed by the subtractive method has been described. Without being limited thereto, the conductor layer 3 may be formed using other methods such as a semi-additive method.

(3) Fuel cell using FPC board Next, a fuel cell using the FPC board 1 will be described. 4A is an external perspective view of a fuel cell using the FPC board 1 described above, and FIG. 4B is a cross-sectional view of the drawer portion 5a in a bent state. FIG. 5 is a diagram for explaining the operation in the fuel cell.

  As shown in FIG. 4A, the fuel cell 30 has a rectangular parallelepiped casing 31 composed of half bodies 31a and 31b. The FPC board 1 is sandwiched between the halves 31a and 31b in a state in which the base insulating layer 2 is bent along the bent portion B1 in FIG. 1 with the one surface on which the conductor layer 3 (FIG. 1) is formed inside. Is done.

  The lead-out portions 5a and 5b of the FPC board 1 are drawn out from between the halves 31a and 31b. As a result, the drawer portions 5 a and 5 b are exposed to the outside of the housing 31. In this case, the positions of the drawers 5a and 5b are set so that the drawers 5a and 5b do not overlap each other.

  The lead portions 5a and 5b are bent along the pair of bent portions B2. Specifically, as shown in FIG. 4B, the double-sided adhesive tape 4 is affixed to the lower surface of the inner region 9a, and the pair of outer regions 7a overlap the lower surface of the inner region 9a via the double-sided adhesive tape 4, respectively. Thus, the drawer | drawing-out part 5a is mountain-folded along bending part B2. As described above, the width of the inner region 9a is substantially equal to the sum of the widths of the pair of outer regions 7a. Thereby, the lower surface of the inner region 9a is covered with the pair of outer regions 7a without the outer regions 7a overlapping each other. In this state, the portion of the inner region 9a of the third insulating portion 2d and the portion of the outer region 7a of the third insulating portion 2d are bonded via the double-sided adhesive tape 4.

  Similarly, the drawer portion 5b is bonded by the double-sided pressure-sensitive adhesive tape 4 while being bent along the bent portion B2.

  In this case, the entire plating layer 11a of the lead portion 5a and the whole lead portion 5b are exposed. Terminals of external circuits are connected to the exposed plating layers 11a and 11b. As described above, the lead portions 5a and 5b are arranged so as not to overlap each other. Thereby, the terminal of an external circuit and the drawer | drawing-out parts 5a and 5b can be connected easily and reliably. Thereby, the connection reliability between the external circuit and the FPC board 1 is ensured.

  As shown in FIG. 5, an electrode film 35 is disposed between the current collector 3 a and the current collector 3 b of the bent FPC board 1 in the housing 31. The electrode film 35 includes a fuel electrode 35a, an air electrode 35b, and an electrolyte film 35c. The fuel electrode 35a is formed on one surface of the electrolyte membrane 35c, and the air electrode 35b is formed on the other surface of the electrolyte membrane 35c. The fuel electrode 35 a of the electrode film 35 faces the current collector 3 b of the FPC board 1, and the air electrode 35 b faces the current collector 3 a of the FPC board 1.

  Fuel is supplied to the fuel electrode 35a of the electrode film 35 through the openings H2 and H12 of the FPC board 1. In the present embodiment, methanol is used as the fuel. Air is supplied to the air electrode 35b of the electrode film 35 through the openings H1 and H11 of the FPC board 1. In this case, methanol is decomposed into hydrogen ions and carbon dioxide in the fuel electrode 35a, and electrons are generated.

  Since the coating layers 6a and 6b of the FPC board 1 contain carbon, conductivity between the electrode film 35 and the current collector 3a is ensured. Therefore, the electrons generated at the fuel electrode 35a are guided from the current collecting portion 3b of the FPC board 1 to the extraction electrode portion 10b (FIG. 4A) through the extraction conductor portion 8b (FIG. 1). Hydrogen ions decomposed from methanol pass through the electrolyte membrane 35c and reach the air electrode 35b. In the air electrode 35b, hydrogen ions react with oxygen while consuming electrons guided from the extraction electrode portion 10a (FIG. 4A) to the current collector 3a via the extraction conductor portion 8a (FIG. 1), Water is produced. In this way, power is supplied to the external circuit connected to the lead portions 5a and 5b.

(4) Effects of the present embodiment When a current flows through the extraction electrode portions 10a and 10b, the heat generation of the extraction electrode portions 10a and 10b increases as the resistance values of the extraction electrode portions 10a and 10b increase. The resistance values of the extraction electrode portions 10a and 10b are inversely proportional to the area of the cross section (the cross section of FIG. 1C) of the extraction electrode portions 10a and 10b perpendicular to the direction in which the current flows. Therefore, the heat generation of the extraction electrode portions 10a and 10b increases as the width of the extraction electrode portions 10a and 10b decreases.

  Therefore, in the FPC board 1 of the present embodiment, the width of the lead electrode portion 10a is set larger than the width of the lead conductor portion 4a, and the width of the lead electrode portion 10b is set larger than the width of the lead conductor portion 4b. Is done. In this case, the resistance values of the extraction electrode portions 10a and 10b can be made sufficiently low.

  Thereby, the heat_generation | fever in extraction electrode part 10a, 10b can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell 30 from being reduced due to heat generated by the extraction electrode portions 10a and 10b. Further, it is possible to prevent the peripheral portions of the extraction electrode portions 10a and 10b from being deformed by the heat generation of the extraction electrode portions 10a and 10b.

  Further, in the FPC board 1 of the present embodiment, the lead-out portions 5a and 5b are bent along the bent portion B2. Thereby, the occupation space of the drawer | drawing-out parts 5a and 5b is reduced. As a result, the degree of freedom of arrangement of the fuel cell 30 using the FPC board 1 is improved.

(5) Modified Examples of Drawer Part Hereinafter, modified examples of the drawer parts 5a and 5b will be described. 6, 7 and 8 are a plan view and a cross-sectional view showing first, second and third modifications of the lead portion 5a. The lead portion 5b has a configuration similar to that of the lead portion 5a shown in FIGS.

(5-1) First Modification The drawing portion 5a shown in FIG. 6 is different from the drawing portion 5a shown in FIG. 1 in the following points.

  In the example of FIG. 6, only one outer region 7a is provided on one side of the inner region 9a. The width of the outer region 7a is set substantially equal to the width of the inner region 9a.

  As shown in FIG. 6B, the double-sided adhesive tape 4 is affixed to the lower surface of the inner region 9a, and the drawer portion 5a is folded so that the outer region 7a overlaps the lower surface of the inner region 9a via the double-sided adhesive tape 4. It is bent along the curved part B1. In this case, the lower surface of the inner region 9a is covered with one outer region 7a. In this state, the portion of the inner region 9a of the third insulating portion 2d and the portion of the outer region 7a of the third insulating portion 2d are bonded via the double-sided adhesive tape 4.

  Also in this example, the width of the extraction electrode portion 10a is set larger than the width of the extraction conductor portion 4a, and the width of the extraction electrode portion 10b is set larger than the width of the extraction conductor portion 4b. Thereby, the resistance values of the extraction electrode portions 10a and 10b can be sufficiently reduced.

  Accordingly, heat generation at the extraction electrode portions 10a and 10b can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell 30 from being reduced due to heat generated by the extraction electrode portions 10a and 10b. Further, it is possible to prevent the peripheral portions of the extraction electrode portions 10a and 10b from being deformed by the heat generation of the extraction electrode portions 10a and 10b.

  In addition, since the lead portions 5a and 5b are bent along the bent portion B2, the space occupied by the lead portions 5a and 5b is reduced. As a result, the degree of freedom of arrangement of the fuel cell 30 using the FPC board 1 is improved.

(5-2) Second Modification The drawing portion 5a shown in FIG. 7 is different from the drawing portion 5a shown in FIG. 6 in the following points. In the example of FIG. 7, the width of the outer region 7a is set to twice the width of the inner region 9a.

  Further, a bent portion B3 is provided along the edge direction so as to bisect the outer region 7a. Hereinafter, the region of the outer region 7a between the bent portion B2 and the bent portion B3 is referred to as an intermediate region 71, and the region of the outer region 7a outside the bent portion B3 is referred to as an end region 72.

  Note that the bent portion B3 may be, for example, a linear shallow groove, or may be a linear mark or the like, similar to the bent portions B1, B2. Or as long as drawer | drawing-out part 5a, 5b can be bent in bending part B2, there may be nothing in bending part B3.

  As shown in FIG. 7B, the double-sided adhesive tape 4a is affixed to the lower surface of the inner region 9a, and the drawer portion 5a is folded so that the intermediate region 71 overlaps the lower surface of the inner region 9a via the double-sided adhesive tape 4a. The mountain is folded along the curved portion B2. In this state, the portion of the inner region 9a of the third insulating portion 2d and the portion of the intermediate region 71 of the third insulating portion 2d are bonded via the double-sided adhesive tape 4a.

  In addition, the double-sided adhesive tape 4b is affixed to the lower surface of the intermediate region 71, and the lead-out portion 5a is valleyd along the bent portion B3 so that the end region 72 overlaps the lower surface of the intermediate region 71 via the double-sided adhesive tape 4b. It is folded. In this state, the intermediate region 71 portion of the plating layer 11a and the end region 72 portion of the plating layer 11a are bonded via the double-sided adhesive tape 4b.

  In this case, a portion of the inner region 9a of the plating layers 11a and 11b is exposed. Terminals of external circuits are connected to the exposed portions of the plated layers 11a and 11b.

  Moreover, the drawer | drawing-out part 5a of Fig.7 (a) may be bent as follows. FIG. 7C shows another example of bending of the drawer portion 5a.

  In the example of FIG. 7, the double-sided adhesive tape 4d is affixed to the lower surface of the intermediate region 71, and the lead-out portion 5a is bent B3 so that the intermediate region 71 and the end region 72 overlap each other via the double-sided adhesive tape 4d. Folded along. In this state, the end region 72 portion of the third insulating portion 2d and the intermediate region 71 portion of the third insulating portion 2d are bonded via the double-sided adhesive tape 4d.

  Further, the double-sided adhesive tape 4c is affixed to the lower surface of the inner region 9a, and the lead-out portion 5a is bent at the bent portion B2 such that the intermediate region 71 and the end region 72 overlap the lower surface of the inner region 9a via the double-sided adhesive tape 4c. Folded along. In this state, the portion of the inner region 9a of the third insulating portion 2d and the portion of the end region 72 of the plating layer 11a are bonded via the double-sided adhesive tape 4c.

  In this case, the inner region 9a and the intermediate region 71 of the plating layers 11a and 11b are exposed. Terminals of external circuits are connected to the exposed portions of the plated layers 11a and 11b.

  Also in this example, the width of the extraction electrode portion 10a is set larger than the width of the extraction conductor portion 4a, and the width of the extraction electrode portion 10b is set larger than the width of the extraction conductor portion 4b. Thereby, the resistance values of the extraction electrode portions 10a and 10b can be sufficiently reduced.

  Further, the width of the extraction electrode portion 10a is larger than that in the example of FIG. Thereby, the resistance values of the extraction electrode portions 10a and 10b can be made sufficiently lower.

  Accordingly, heat generation at the extraction electrode portions 10a and 10b can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell 30 from being reduced due to heat generated by the extraction electrode portions 10a and 10b. Further, it is possible to prevent the peripheral portions of the extraction electrode portions 10a and 10b from being deformed by the heat generation of the extraction electrode portions 10a and 10b.

  In addition, since the drawer portions 5a and 5b are bent along the bent portions B2 and B3, the space occupied by the drawer portions 5a and 5b is reduced. As a result, the degree of freedom of arrangement of the fuel cell 30 using the FPC board 1 is improved.

(5-3) Third Modification The drawing portion 5a shown in FIG. 8 is different from the drawing portion 5a shown in FIG. 1 in the following points. In the example of FIG. 8, the width of the inner region 9a is substantially equal to the width of each of the outer regions 7a.

  As shown in FIG. 8 (b), the double-sided adhesive tape 4e is affixed to the lower surface of the inner region 9a, and the drawer portion 5a is arranged such that one outer region 7a overlaps the lower surface of the inner region 9a via the double-sided adhesive tape 4e. Is mountain-folded along one bent portion B2. In that state, the portion of the inner region 9a of the third insulating portion 2d and the portion of one inner region 9a of the third insulating portion 2d are bonded via the double-sided adhesive tape 4e.

  Further, the double-sided adhesive tape 4f is affixed to the lower surface of one outer region 7a, and the drawer portion 5a is folded in the other direction so that the other outer region 7a overlaps the lower surface of one outer region 7a via the double-sided adhesive tape 4f. The mountain is folded along the curved portion B2. In this state, the portion of one outer region 7a of the plating layer 11a and the portion of the other outer region 7a of the third insulating portion 2d are bonded via the double-sided adhesive tape 4f.

  In this case, the inner region 9a and the one outer region 7a of the plating layers 11a and 11b are exposed. Terminals of external circuits are connected to the exposed portions of the plated layers 11a and 11b.

  Also in this example, the width of the extraction electrode portion 10a is set larger than the width of the extraction conductor portion 4a, and the width of the extraction electrode portion 10b is set larger than the width of the extraction conductor portion 4b. Thereby, the resistance values of the extraction electrode portions 10a and 10b can be sufficiently reduced.

  Further, the width of the extraction electrode portion 10a is larger than that in the example of FIG. Thereby, the resistance values of the extraction electrode portions 10a and 10b can be made sufficiently lower.

  Accordingly, heat generation at the extraction electrode portions 10a and 10b can be suppressed. As a result, it is possible to prevent the power generation efficiency of the fuel cell 30 from being reduced due to heat generated by the extraction electrode portions 10a and 10b. Further, it is possible to prevent the peripheral portions of the extraction electrode portions 10a and 10b from being deformed by the heat generation of the extraction electrode portions 10a and 10b.

  In addition, since the lead portions 5a and 5b are bent along the bent portion B2, the space occupied by the lead portions 5a and 5b is reduced. As a result, the degree of freedom of arrangement of the fuel cell 30 using the FPC board 1 is improved.

(6) Other Modifications FIG. 9 is a plan view showing another modification of the FPC board 1. The FPC board 1a shown in FIG. 9 is different from the FPC board 1 of FIG. 1 in the following points.

  In the example of FIG. 9, the fourth insulating portion 2g is provided so as to protrude outward from the side of the first region of the first insulating portion 2c, and the fourth insulating portion is protruded outward from the side of the second region. A portion 2h is provided. The widths of the fourth insulating portions 2g and 2h are set so as to gradually increase toward the outside. Here, the width of the fourth insulating portions 2g and 2h refers to the length of the fourth insulating portions 2g and 2h in the side direction.

  Third insulating portions 2d and 2e are provided at the distal ends of the fourth insulating portions 2g and 2h. The widths of the third insulating portions 2d and 2e are equal to the widths of the tips of the fourth insulating portions 2g and 2h.

  Current collectors 3a and 3b are provided so as to be close to the side of the first insulating part 2c. Cover layers 6a and 6b are provided on the first insulating portion 2c so as to cover the current collecting portions 3a and 3b, respectively. The connecting conductor portions 14a and 14b are formed to extend from the sides of the current collecting portions 3a and 3b to the third insulating portions 2d and 2e through the first insulating portion 2c and the fourth insulating portions 2g and 2h, respectively. The

  The widths of the connecting conductor portions 14a and 14b are set so as to gradually increase toward the outside. Here, the widths of the connecting conductor portions 14a and 14b refer to the lengths of the connecting conductor portions 14a and 14b in the side direction. In addition, it is preferable that the length of the connection conductor parts 14a and 14b in the edge direction is smaller. Thereby, the resistance value in connection conductor part 14a, 14b can be made lower.

  On the third insulating portions 2d and 2e, lead electrode portions 10a and 10b are formed integrally with the tip portions of the connecting conductor portions 14a and 14b. A plating layer 11a is formed on the third insulating portions 2d and 2e and on the fourth insulating portions 2g and 2h so as to cover the portions of the connecting conductor portions 14a and 14b on the lead electrode portions 10a and 10b and the fourth insulating portions 2g and 2h. 11b are formed.

  In this example, the lead conductor portions 15a and 15b are configured by the portions of the connecting conductor portions 14a and 14b provided on the first insulating portion 2c. In addition, lead electrode portions 16a and 16b are respectively constituted by the connecting conductor portions 14a and 14b provided on the fourth insulating portions 2g and 2h and the lead electrode portions 10a and 10b. In this case, the maximum width of the extraction electrode portions 16a and 16b is larger than the maximum width of the extraction conductor portions 15a and 15b.

  The third insulating portions 2d and 2e, the fourth insulating portions 2g and 2h, the lead conductor portions 15a and 15b, and the lead electrode portions 16a and 16b constitute lead portions 17a and 17b, respectively.

  In the lead-out part 17a so as to extend in the end side direction through the intersection of the two sides of the fourth insulating part 2g and the side of the first insulating part 2c inclined with respect to the side of the first insulating part 2c. A pair of bent portions B2 are provided. Similarly, the lead-out portion extends in the end direction through the intersection of the two sides of the fourth insulating portion 2h and the side of the first insulating portion 2c, which are inclined with respect to the side of the first insulating portion 2c. A pair of bent portions B2 is provided at 17b. The lead-out portions 17a and 17b are bent along the pair of bent portions B2.

  With such a configuration, the resistance value in the lead conductor portions 15a and 15b can be lowered. Thereby, heat generation in the lead conductor portions 15a and 15b can be suppressed.

(7) Examples and Comparative Examples (7-1) Example 1
As Example 1, FPC board 1 having the same configuration as that of FIG. 1 was produced except that coating layers 6a and 6b, insulating cover layers 8a and 8b, and plating layers 11a and 11b were not provided.

  In addition, polyimide was used as the material of the base insulating layer 2, and copper was used as the material of the conductor layer 3. Moreover, the thickness of the base insulating layer 2 was 25 μm, and the thickness of the conductor layer 3 was 35 μm.

  In addition, the width of the lead conductor portions 4a and 4b was 7 mm, the width of the lead electrode portions 10a and 10b was 14 mm, and the length in the end side direction of the lead electrode portions 10a and 10b was 60 mm.

  In this FPC board 1, as shown in FIG. 4B, the lead-out portions 5a and 5b were fixed by the double-sided adhesive tape 4 in a state of being bent along the bent portion B2.

(7-2) Example 2
As Example 2, an FPC board 1 similar to that of Example 1 was manufactured except that the lead portions 5a and 5b have the configuration shown in FIG.

  The width of the lead conductor portions 4a and 4b was 7 mm, the width of the lead electrode portions 10a and 10b was 14 mm, and the length in the end side direction of the lead electrode portions 10a and 10b was 60 mm.

  In this FPC board 1, as shown in FIG. 6B, the lead-out portions 5a and 5b were fixed by the double-sided adhesive tape 4 in a state of being bent along the bent portion B2.

(7-3) Example 3
As Example 3, an FPC board 1 similar to that of Example 1 was manufactured except that the lead portions 5a and 5b have the configuration shown in FIG.

  The width of the lead conductor portions 4a and 4b was 7 mm, the width of the lead electrode portions 10a and 10b was 21.3 mm, and the length in the edge direction of the lead electrode portions 10a and 10b was 60 mm.

  In this FPC board 1, as shown in FIG. 7B, the lead-out portions 5a and 5b were fixed by the double-sided adhesive tapes 4a and 4b in a state of being bent along the bent portions B2 and B3.

(7-4) Example 4
As Example 4, an FPC board 1 similar to that of Example 1 was manufactured except that the lead portions 5a and 5b have the configuration shown in FIG.

  The width of the lead conductor portions 4a and 4b was 7 mm, the width of the lead electrode portions 10a and 10b was 21.3 mm, and the length in the edge direction of the lead electrode portions 10a and 10b was 60 mm.

  In this FPC board 1, as shown in FIG. 7C, the lead-out portions 5a and 5b were fixed by double-sided adhesive tapes 4c and 4d in a state of being bent along the bent portions B2 and B3.

(7-5) Example 5
As Example 5, an FPC board 1 similar to that of Example 1 was manufactured except that the lead portions 5a and 5b have the configuration shown in FIG.

  The width of the lead conductor portions 4a and 4b was 7 mm, the width of the lead electrode portions 10a and 10b was 21.3 mm, and the length in the edge direction of the lead electrode portions 10a and 10b was 60 mm.

  In this FPC board 1, as shown in FIG. 8 (b), the lead-out portions 5a and 5b were fixed by double-sided adhesive tapes 4e and 4f in a state of being bent along the bent portions B2 and B3.

(7-6) Comparative Example As a comparative example, an FPC board 1 similar to that of Example 1 was manufactured except that the width of the extraction electrode portions 10a and 10b was set to 7 mm, which was equal to the extraction conductor portions 4a and 4b.

(7-7) Evaluation In the FPC boards 1 of Examples 1 to 5 and the comparative example, a current of 5A was passed through the extraction electrode portions 10a and 10b for 5 minutes, and the temperatures of the subsequent extraction electrode portions 10a and 10b were measured. The initial temperature of the extraction electrode portions 10a and 10b was 20 ° C.

  In the FPC board 1 of Example 1, the average value of the temperature of the extraction electrode portions 10a and 10b after flowing current was 25.3 ° C. In the FPC board 1 of Example 2, the average value of the temperatures of the extraction electrode portions 10a and 10b after flowing current was 25.3 ° C. In the FPC board 1 of Example 3, the average value of the temperature of the extraction electrode portions 10a and 10b after flowing current was 24.0 ° C. In the FPC board 1 of Example 4, the average value of the temperatures of the extraction electrode portions 10a and 10b after flowing current was 24.0 ° C. In the FPC board 1 of Example 5, the average value of the temperatures of the extraction electrode portions 10a and 10b after flowing current was 25.3 ° C.

  On the other hand, in the FPC board 1 of the comparative example, the average value of the temperatures of the extraction electrode portions 10a and 10b after flowing current was 33.0 ° C.

  Thus, in the FPC boards 1 of Examples 1 to 5, the temperature difference between the extraction electrode portions 10a and 10b before and after the current flow was 4.0 to 5.3 ° C. On the other hand, in the FPC board 1 of the comparative example, the temperature difference between the extraction electrode portions 10a and 10b before and after the current flow was 13.0 ° C.

  From this, it was found that heat generation in the extraction electrode portions 10a and 10b is sufficiently suppressed by setting the width of the extraction electrode portions 10a and 10b to be larger than the width of the extraction conductor portions 4a and 4b. Thereby, it is possible to prevent the power generation efficiency of the fuel cell 30 from being lowered due to the heat generation of the extraction electrode portions 10a and 10b, and the peripheral portions of the extraction electrode portions 10a and 10b are caused by the heat generation of the extraction electrode portions 10a and 10b. It has been found that deformation can be prevented.

(8) Correspondence between each component of claim and each part of embodiment The following describes an example of the correspondence between each component of the claim and each part of the embodiment. It is not limited.

  In the above embodiment, the FPC board 1 is an example of a printed circuit board, the conductor layer 3 is an example of a conductor layer, the current collectors 3a and 3b are examples of current collectors, the lead conductors 4a, 4b, 15a, 15b are examples of the lead conductor part, lead electrode parts 10a, 10b, 16a, 16b are examples of the lead electrode part, the edge direction is an example of the extending direction of the lead conductor part, The regions 9a and 9b are examples of the first portion, the intermediate region 71 is an example of the second portion, the end region 72 is an example of the third portion, and the outer regions 7a and 7b are the fourth portion. This is an example of the portion, the current collector 3a is an example of the first current collector, the current collector 3b is an example of the second current collector, and the lead conductor 4a is the first lead conductor. The lead conductor portion 4b is an example of the second lead conductor portion, and the lead electrode portion 10a. An example of the first lead electrode portions, lead-out electrode portion 10b is an example of a second lead-out electrode portion, the electrode film 35 is an example of the battery element, the housing 31 is an example of the housing.

  As each constituent element in the claims, various other elements having configurations or functions described in the claims can be used.

  The present invention can be effectively used for various printed circuit boards used in fuel cells.

DESCRIPTION OF SYMBOLS 1 FPC board 2 Base insulating layer 2a, 2b 2nd insulating part 2c 1st insulating part 2d, 2e 3rd insulating part 3 Conductor layer 3a, 3b Current collecting part 4a, 4b Leading conductor part 5a, 5b Leading part 6a, 6b Cover Layer 7a, 7b Outer region 8a, 8b Cover insulating layer 9a, 9b Inner region 10a, 10b Lead electrode part 11a, 11b Plating layer 20 Insulating film 21 Conductor film 22 Etching resist 23 Cover film 31 Housing 31a, 31b Half body 35 Electrode film 35a Fuel electrode 35b Air electrode 35c Electrolyte film 71 Intermediate area 72 End area B1, B2 Bending part H1, H2, H11, H12 Opening

Claims (10)

A printed circuit board used for a fuel cell,
An insulating layer;
A conductor layer provided on the insulating layer;
The conductor layer is
Current collector,
A lead conductor extending from the current collector;
A lead electrode portion provided at a tip portion of the lead conductor portion;
A printed circuit board, wherein a maximum width of the lead electrode portion is larger than a maximum width of the lead conductor portion. 2. The printed circuit board according to claim 1, wherein the lead electrode part is configured to be bendable along one or a plurality of lines substantially parallel to the extending direction of the lead conductor part. The lead electrode portion is
A first portion having a width equal to that of the lead conductor portion and extending from the lead conductor portion in the extending direction;
A second portion provided on one side of the first portion,
3. The printed circuit board according to claim 1, wherein the printed circuit board is configured to be bendable along a boundary line between the first portion and the second portion. 4. The printed circuit board according to claim 3, wherein the width of the second portion is equal to the width of the first portion. The lead electrode portion is
A third portion provided on a further side of the second portion and having a width equal to the first portion;
5. The printed circuit board according to claim 4, wherein the printed circuit board is configured to be bendable along a boundary line between the second portion and the third portion. The lead electrode portion is
A fourth portion provided on the other side of the first portion;
4. The printed circuit board according to claim 3, wherein the printed circuit board is configured to be bendable along a boundary line between the first portion and the fourth portion. 7. The printed circuit board according to claim 6, wherein the sum of the width of the second portion and the width of the fourth portion is equal to the width of the first portion. 7. The printed circuit board according to claim 6, wherein the width of each of the second portion and the fourth portion is equal to the width of the first portion. A printed circuit board used for a fuel cell,
An insulating layer;
A conductor layer provided on the insulating layer;
The conductor layer is
First and second current collectors;
First and second lead conductor portions extending from the first and second current collectors, respectively;
First and second lead electrode portions respectively provided at the tip ends of the first and second lead conductor portions;
The insulating layer and the conductor layer are configured to be bendable between the first and second current collectors so that the conductor layer is located inside,
A printed circuit board, wherein the maximum width of the first and second lead electrode portions is larger than the maximum width of the first and second lead conductor portions, respectively. A battery element;
The printed circuit board according to claim 9,
A housing for housing the printed circuit board and the battery element;
The wired circuit board is housed in the housing with the battery element sandwiched between the first current collector and the second current collector, and the first and second drawers A fuel cell, wherein the electrode portions are drawn out from the housing so as not to overlap each other.

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